hw/misc/led: Add yellow LED
[qemu/ar7.git] / os-posix.c
bloba6846f51c173690a2cbd8a56cee398536eff3db8
1 /*
2 * os-posix.c
4 * Copyright (c) 2003-2008 Fabrice Bellard
5 * Copyright (c) 2010 Red Hat, Inc.
7 * Permission is hereby granted, free of charge, to any person obtaining a copy
8 * of this software and associated documentation files (the "Software"), to deal
9 * in the Software without restriction, including without limitation the rights
10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11 * copies of the Software, and to permit persons to whom the Software is
12 * furnished to do so, subject to the following conditions:
14 * The above copyright notice and this permission notice shall be included in
15 * all copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23 * THE SOFTWARE.
26 #include "qemu/osdep.h"
27 #include <sys/wait.h>
28 #include <pwd.h>
29 #include <grp.h>
30 #include <libgen.h>
32 #include "qemu-common.h"
33 /* Needed early for CONFIG_BSD etc. */
34 #include "net/slirp.h"
35 #include "qemu-options.h"
36 #include "qemu/error-report.h"
37 #include "qemu/log.h"
38 #include "sysemu/runstate.h"
39 #include "qemu/cutils.h"
41 #ifdef CONFIG_LINUX
42 #include <sys/prctl.h>
43 #endif
46 * Must set all three of these at once.
47 * Legal combinations are unset by name by uid
49 static struct passwd *user_pwd; /* NULL non-NULL NULL */
50 static uid_t user_uid = (uid_t)-1; /* -1 -1 >=0 */
51 static gid_t user_gid = (gid_t)-1; /* -1 -1 >=0 */
53 static const char *chroot_dir;
54 static int daemonize;
55 static int daemon_pipe;
57 void os_setup_early_signal_handling(void)
59 struct sigaction act;
60 sigfillset(&act.sa_mask);
61 act.sa_flags = 0;
62 act.sa_handler = SIG_IGN;
63 sigaction(SIGPIPE, &act, NULL);
66 static void termsig_handler(int signal, siginfo_t *info, void *c)
68 qemu_system_killed(info->si_signo, info->si_pid);
71 void os_setup_signal_handling(void)
73 struct sigaction act;
75 memset(&act, 0, sizeof(act));
76 act.sa_sigaction = termsig_handler;
77 act.sa_flags = SA_SIGINFO;
78 sigaction(SIGINT, &act, NULL);
79 sigaction(SIGHUP, &act, NULL);
80 sigaction(SIGTERM, &act, NULL);
83 void os_set_proc_name(const char *s)
85 #if defined(PR_SET_NAME)
86 char name[16];
87 if (!s)
88 return;
89 pstrcpy(name, sizeof(name), s);
90 /* Could rewrite argv[0] too, but that's a bit more complicated.
91 This simple way is enough for `top'. */
92 if (prctl(PR_SET_NAME, name)) {
93 error_report("unable to change process name: %s", strerror(errno));
94 exit(1);
96 #else
97 error_report("Change of process name not supported by your OS");
98 exit(1);
99 #endif
103 static bool os_parse_runas_uid_gid(const char *optarg)
105 unsigned long lv;
106 const char *ep;
107 uid_t got_uid;
108 gid_t got_gid;
109 int rc;
111 rc = qemu_strtoul(optarg, &ep, 0, &lv);
112 got_uid = lv; /* overflow here is ID in C99 */
113 if (rc || *ep != ':' || got_uid != lv || got_uid == (uid_t)-1) {
114 return false;
117 rc = qemu_strtoul(ep + 1, 0, 0, &lv);
118 got_gid = lv; /* overflow here is ID in C99 */
119 if (rc || got_gid != lv || got_gid == (gid_t)-1) {
120 return false;
123 user_pwd = NULL;
124 user_uid = got_uid;
125 user_gid = got_gid;
126 return true;
130 * Parse OS specific command line options.
131 * return 0 if option handled, -1 otherwise
133 int os_parse_cmd_args(int index, const char *optarg)
135 switch (index) {
136 case QEMU_OPTION_runas:
137 user_pwd = getpwnam(optarg);
138 if (user_pwd) {
139 user_uid = -1;
140 user_gid = -1;
141 } else if (!os_parse_runas_uid_gid(optarg)) {
142 error_report("User \"%s\" doesn't exist"
143 " (and is not <uid>:<gid>)",
144 optarg);
145 exit(1);
147 break;
148 case QEMU_OPTION_chroot:
149 chroot_dir = optarg;
150 break;
151 case QEMU_OPTION_daemonize:
152 daemonize = 1;
153 break;
154 #if defined(CONFIG_LINUX)
155 case QEMU_OPTION_enablefips:
156 warn_report("-enable-fips is deprecated, please build QEMU with "
157 "the `libgcrypt` library as the cryptography provider "
158 "to enable FIPS compliance");
159 fips_set_state(true);
160 break;
161 #endif
162 default:
163 return -1;
166 return 0;
169 static void change_process_uid(void)
171 assert((user_uid == (uid_t)-1) || user_pwd == NULL);
172 assert((user_uid == (uid_t)-1) ==
173 (user_gid == (gid_t)-1));
175 if (user_pwd || user_uid != (uid_t)-1) {
176 gid_t intended_gid = user_pwd ? user_pwd->pw_gid : user_gid;
177 uid_t intended_uid = user_pwd ? user_pwd->pw_uid : user_uid;
178 if (setgid(intended_gid) < 0) {
179 error_report("Failed to setgid(%d)", intended_gid);
180 exit(1);
182 if (user_pwd) {
183 if (initgroups(user_pwd->pw_name, user_pwd->pw_gid) < 0) {
184 error_report("Failed to initgroups(\"%s\", %d)",
185 user_pwd->pw_name, user_pwd->pw_gid);
186 exit(1);
188 } else {
189 if (setgroups(1, &user_gid) < 0) {
190 error_report("Failed to setgroups(1, [%d])",
191 user_gid);
192 exit(1);
195 if (setuid(intended_uid) < 0) {
196 error_report("Failed to setuid(%d)", intended_uid);
197 exit(1);
199 if (setuid(0) != -1) {
200 error_report("Dropping privileges failed");
201 exit(1);
206 static void change_root(void)
208 if (chroot_dir) {
209 if (chroot(chroot_dir) < 0) {
210 error_report("chroot failed");
211 exit(1);
213 if (chdir("/")) {
214 error_report("not able to chdir to /: %s", strerror(errno));
215 exit(1);
221 void os_daemonize(void)
223 if (daemonize) {
224 pid_t pid;
225 int fds[2];
227 if (pipe(fds) == -1) {
228 exit(1);
231 pid = fork();
232 if (pid > 0) {
233 uint8_t status;
234 ssize_t len;
236 close(fds[1]);
238 do {
239 len = read(fds[0], &status, 1);
240 } while (len < 0 && errno == EINTR);
242 /* only exit successfully if our child actually wrote
243 * a one-byte zero to our pipe, upon successful init */
244 exit(len == 1 && status == 0 ? 0 : 1);
246 } else if (pid < 0) {
247 exit(1);
250 close(fds[0]);
251 daemon_pipe = fds[1];
252 qemu_set_cloexec(daemon_pipe);
254 setsid();
256 pid = fork();
257 if (pid > 0) {
258 exit(0);
259 } else if (pid < 0) {
260 exit(1);
262 umask(027);
264 signal(SIGTSTP, SIG_IGN);
265 signal(SIGTTOU, SIG_IGN);
266 signal(SIGTTIN, SIG_IGN);
270 void os_setup_post(void)
272 int fd = 0;
274 if (daemonize) {
275 if (chdir("/")) {
276 error_report("not able to chdir to /: %s", strerror(errno));
277 exit(1);
279 TFR(fd = qemu_open_old("/dev/null", O_RDWR));
280 if (fd == -1) {
281 exit(1);
285 change_root();
286 change_process_uid();
288 if (daemonize) {
289 uint8_t status = 0;
290 ssize_t len;
292 dup2(fd, 0);
293 dup2(fd, 1);
294 /* In case -D is given do not redirect stderr to /dev/null */
295 if (!qemu_logfile) {
296 dup2(fd, 2);
299 close(fd);
301 do {
302 len = write(daemon_pipe, &status, 1);
303 } while (len < 0 && errno == EINTR);
304 if (len != 1) {
305 exit(1);
310 void os_set_line_buffering(void)
312 setvbuf(stdout, NULL, _IOLBF, 0);
315 bool is_daemonized(void)
317 return daemonize;
320 int os_mlock(void)
322 #ifdef HAVE_MLOCKALL
323 int ret = 0;
325 ret = mlockall(MCL_CURRENT | MCL_FUTURE);
326 if (ret < 0) {
327 error_report("mlockall: %s", strerror(errno));
330 return ret;
331 #else
332 return -ENOSYS;
333 #endif